1. Technical Field
The present invention relates to a semiconductor device, a method of manufacturing a semiconductor device, an electroluminescence device, and a method of manufacturing an electroluminescence device.
2. Related Art
In recent years, a method of manufacturing an electro-optical device has been developed (see Japanese Unexamined Patent Publication No. 2002-082633) as a way to join two different types of boards together to manufacture a joined board. According to this method, an electro-optical device is manufactured by joining an electro-optical board provided with a light-emitting element, such as an organic electroluminescence (EL) device, and a driving circuit board (semiconductor device) provided with a driving element that makes the light emitting element emit light.
In this method of manufacturing a joined board, an electro-optical board and a driving circuit board are separately provided and then the two boards are joined together to form an electro-optical device. Therefore, a process required for forming the driving circuit board after forming or printing a driving element, such as a thin-film transistor (TFT), can be reduced, and thereby significantly reduce the possibility of damaging the driving element during the manufacturing process. Also, since the electro-optical board and the driving circuit board are manufactured in separate steps, the yield can be increased. It is also possible to join an electro-optical board and a driving circuit board manufactured by different plants or manufacturers, which is highly advantageous in reducing manufacturing costs. Also, it is possible to manufacture a wide-screen electro-optical device with a comparatively low investment in a plant and equipment.
According to Publication No. 2002-082633, a TFT is printed and conductively coupled on a wiring board that is wired with an anisotropic conductive paste (ACP). This structure, however, may cause a defective contact between the wiring board and the TFT due to variations in the height of the bumps on the wiring board.
Also, since a narrow gap between the TFT pads may cause a short-circuit between neighboring pads with an ACP therebetween, the TFT size and the number of terminals are limited.
Furthermore, when conductive coupling the wiring board and the TFT, a load imposed on the TFT for coupling the wiring board and the TFT with the ACP is so large that a crack may develop in the TFT.
In order to address the above-mentioned problems, the present invention provides a semiconductor device, a method of manufacturing a semiconductor device, an EL device using a semiconductor device, and a method of manufacturing an EL device that can ensure a narrow pitch between the pads of semiconductor elements, e.g. the TFT, improve conductivity to the semiconductor elements, and prevent damage to the semiconductor elements.